tools/perf/util/config.c

   1 /*
   2  * config.c
   3  *
   4  * Helper functions for parsing config items.
   5  * Originally copied from GIT source.
   6  *
   7  * Copyright (C) Linus Torvalds, 2005
   8  * Copyright (C) Johannes Schindelin, 2005
   9  *
  10  */
  11 #include "util.h"
  12 #include "cache.h"
  13 #include <subcmd/exec-cmd.h>
  14 #include "util/hist.h"  /* perf_hist_config */
  15 #include "util/llvm-utils.h"   /* perf_llvm_config */
  16 #include "config.h"
  17
  18 #define MAXNAME (256)
  19
  20 #define DEBUG_CACHE_DIR ".debug"
  21
  22
  23 char buildid_dir[MAXPATHLEN]; /* root dir for buildid, binary cache */
  24
  25 static FILE *config_file;
  26 static const char *config_file_name;
  27 static int config_linenr;
  28 static int config_file_eof;
  29 static struct perf_config_set *config_set;
  30
  31 const char *config_exclusive_filename;
  32
  33 static int get_next_char(void)
  34 {
  35         int c;
  36         FILE *f;
  37
  38         c = '\n';
  39         if ((f = config_file) != NULL) {
  40                 c = fgetc(f);
  41                 if (c == '\r') {
  42                         /* DOS like systems */
  43                         c = fgetc(f);
  44                         if (c != '\n') {
  45                                 ungetc(c, f);
  46                                 c = '\r';
  47                         }
  48                 }
  49                 if (c == '\n')
  50                         config_linenr++;
  51                 if (c == EOF) {
  52                         config_file_eof = 1;
  53                         c = '\n';
  54                 }
  55         }
  56         return c;
  57 }
  58
  59 static char *parse_value(void)
  60 {
  61         static char value[1024];
  62         int quote = 0, comment = 0, space = 0;
  63         size_t len = 0;
  64
  65         for (;;) {
  66                 int c = get_next_char();
  67
  68                 if (len >= sizeof(value) - 1)
  69                         return NULL;
  70                 if (c == '\n') {
  71                         if (quote)
  72                                 return NULL;
  73                         value[len] = 0;
  74                         return value;
  75                 }
  76                 if (comment)
  77                         continue;
  78                 if (isspace(c) && !quote) {
  79                         space = 1;
  80                         continue;
  81                 }
  82                 if (!quote) {
  83                         if (c == ';' || c == '#') {
  84                                 comment = 1;
  85                                 continue;
  86                         }
  87                 }
  88                 if (space) {
  89                         if (len)
  90                                 value[len++] = ' ';
  91                         space = 0;
  92                 }
  93                 if (c == '\\') {
  94                         c = get_next_char();
  95                         switch (c) {
  96                         case '\n':
  97                                 continue;
  98                         case 't':
  99                                 c = '\t';
 100                                 break;
 101                         case 'b':
 102                                 c = '\b';
 103                                 break;
 104                         case 'n':
 105                                 c = '\n';
 106                                 break;
 107                         /* Some characters escape as themselves */
 108                         case '\\': case '"':
 109                                 break;
 110                         /* Reject unknown escape sequences */
 111                         default:
 112                                 return NULL;
 113                         }
 114                         value[len++] = c;
 115                         continue;
 116                 }
 117                 if (c == '"') {
 118                         quote = 1-quote;
 119                         continue;
 120                 }
 121                 value[len++] = c;
 122         }
 123 }
 124
 125 static inline int iskeychar(int c)
 126 {
 127         return isalnum(c) || c == '-' || c == '_';
 128 }
 129
 130 static int get_value(config_fn_t fn, void *data, char *name, unsigned int len)
 131 {
 132         int c;
 133         char *value;
 134
 135         /* Get the full name */
 136         for (;;) {
 137                 c = get_next_char();
 138                 if (config_file_eof)
 139                         break;
 140                 if (!iskeychar(c))
 141                         break;
 142                 name[len++] = c;
 143                 if (len >= MAXNAME)
 144                         return -1;
 145         }
 146         name[len] = 0;
 147         while (c == ' ' || c == '\t')
 148                 c = get_next_char();
 149
 150         value = NULL;
 151         if (c != '\n') {
 152                 if (c != '=')
 153                         return -1;
 154                 value = parse_value();
 155                 if (!value)
 156                         return -1;
 157         }
 158         return fn(name, value, data);
 159 }
 160
 161 static int get_extended_base_var(char *name, int baselen, int c)
 162 {
 163         do {
 164                 if (c == '\n')
 165                         return -1;
 166                 c = get_next_char();
 167         } while (isspace(c));
 168
 169         /* We require the format to be '[base "extension"]' */
 170         if (c != '"')
 171                 return -1;
 172         name[baselen++] = '.';
 173
 174         for (;;) {
 175                 int ch = get_next_char();
 176
 177                 if (ch == '\n')
 178                         return -1;
 179                 if (ch == '"')
 180                         break;
 181                 if (ch == '\\') {
 182                         ch = get_next_char();
 183                         if (ch == '\n')
 184                                 return -1;
 185                 }
 186                 name[baselen++] = ch;
 187                 if (baselen > MAXNAME / 2)
 188                         return -1;
 189         }
 190
 191         /* Final ']' */
 192         if (get_next_char() != ']')
 193                 return -1;
 194         return baselen;
 195 }
 196
 197 static int get_base_var(char *name)
 198 {
 199         int baselen = 0;
 200
 201         for (;;) {
 202                 int c = get_next_char();
 203                 if (config_file_eof)
 204                         return -1;
 205                 if (c == ']')
 206                         return baselen;
 207                 if (isspace(c))
 208                         return get_extended_base_var(name, baselen, c);
 209                 if (!iskeychar(c) && c != '.')
 210                         return -1;
 211                 if (baselen > MAXNAME / 2)
 212                         return -1;
 213                 name[baselen++] = tolower(c);
 214         }
 215 }
 216
 217 static int perf_parse_file(config_fn_t fn, void *data)
 218 {
 219         int comment = 0;
 220         int baselen = 0;
 221         static char var[MAXNAME];
 222
 223         /* U+FEFF Byte Order Mark in UTF8 */
 224         static const unsigned char *utf8_bom = (unsigned char *) "\xef\xbb\xbf";
 225         const unsigned char *bomptr = utf8_bom;
 226
 227         for (;;) {
 228                 int line, c = get_next_char();
 229
 230                 if (bomptr && *bomptr) {
 231                         /* We are at the file beginning; skip UTF8-encoded BOM
 232                          * if present. Sane editors won't put this in on their
 233                          * own, but e.g. Windows Notepad will do it happily. */
 234                         if ((unsigned char) c == *bomptr) {
 235                                 bomptr++;
 236                                 continue;
 237                         } else {
 238                                 /* Do not tolerate partial BOM. */
 239                                 if (bomptr != utf8_bom)
 240                                         break;
 241                                 /* No BOM at file beginning. Cool. */
 242                                 bomptr = NULL;
 243                         }
 244                 }
 245                 if (c == '\n') {
 246                         if (config_file_eof)
 247                                 return 0;
 248                         comment = 0;
 249                         continue;
 250                 }
 251                 if (comment || isspace(c))
 252                         continue;
 253                 if (c == '#' || c == ';') {
 254                         comment = 1;
 255                         continue;
 256                 }
 257                 if (c == '[') {
 258                         baselen = get_base_var(var);
 259                         if (baselen <= 0)
 260                                 break;
 261                         var[baselen++] = '.';
 262                         var[baselen] = 0;
 263                         continue;
 264                 }
 265                 if (!isalpha(c))
 266                         break;
 267                 var[baselen] = tolower(c);
 268
 269                 /*
 270                  * The get_value function might or might not reach the '\n',
 271                  * so saving the current line number for error reporting.
 272                  */
 273                 line = config_linenr;
 274                 if (get_value(fn, data, var, baselen+1) < 0) {
 275                         config_linenr = line;
 276                         break;
 277                 }
 278         }
 279         pr_err("bad config file line %d in %s\n", config_linenr, config_file_name);
 280         return -1;
 281 }
 282
 283 static int parse_unit_factor(const char *end, unsigned long *val)
 284 {
 285         if (!*end)
 286                 return 1;
 287         else if (!strcasecmp(end, "k")) {
 288                 *val *= 1024;
 289                 return 1;
 290         }
 291         else if (!strcasecmp(end, "m")) {
 292                 *val *= 1024 * 1024;
 293                 return 1;
 294         }
 295         else if (!strcasecmp(end, "g")) {
 296                 *val *= 1024 * 1024 * 1024;
 297                 return 1;
 298         }
 299         return 0;
 300 }
 301
 302 static int perf_parse_llong(const char *value, long long *ret)
 303 {
 304         if (value && *value) {
 305                 char *end;
 306                 long long val = strtoll(value, &end, 0);
 307                 unsigned long factor = 1;
 308
 309                 if (!parse_unit_factor(end, &factor))
 310                         return 0;
 311                 *ret = val * factor;
 312                 return 1;
 313         }
 314         return 0;
 315 }
 316
 317 static int perf_parse_long(const char *value, long *ret)
 318 {
 319         if (value && *value) {
 320                 char *end;
 321                 long val = strtol(value, &end, 0);
 322                 unsigned long factor = 1;
 323                 if (!parse_unit_factor(end, &factor))
 324                         return 0;
 325                 *ret = val * factor;
 326                 return 1;
 327         }
 328         return 0;
 329 }
 330
 331 static void die_bad_config(const char *name)
 332 {
 333         if (config_file_name)
 334                 die("bad config value for '%s' in %s", name, config_file_name);
 335         die("bad config value for '%s'", name);
 336 }
 337
 338 u64 perf_config_u64(const char *name, const char *value)
 339 {
 340         long long ret = 0;
 341
 342         if (!perf_parse_llong(value, &ret))
 343                 die_bad_config(name);
 344         return (u64) ret;
 345 }
 346
 347 int perf_config_int(const char *name, const char *value)
 348 {
 349         long ret = 0;
 350         if (!perf_parse_long(value, &ret))
 351                 die_bad_config(name);
 352         return ret;
 353 }
 354
 355 static int perf_config_bool_or_int(const char *name, const char *value, int *is_bool)
 356 {
 357         *is_bool = 1;
 358         if (!value)
 359                 return 1;
 360         if (!*value)
 361                 return 0;
 362         if (!strcasecmp(value, "true") || !strcasecmp(value, "yes") || !strcasecmp(value, "on"))
 363                 return 1;
 364         if (!strcasecmp(value, "false") || !strcasecmp(value, "no") || !strcasecmp(value, "off"))
 365                 return 0;
 366         *is_bool = 0;
 367         return perf_config_int(name, value);
 368 }
 369
 370 int perf_config_bool(const char *name, const char *value)
 371 {
 372         int discard;
 373         return !!perf_config_bool_or_int(name, value, &discard);
 374 }
 375
 376 static const char *perf_config_dirname(const char *name, const char *value)
 377 {
 378         if (!name)
 379                 return NULL;
 380         return value;
 381 }
 382
 383 static int perf_buildid_config(const char *var, const char *value)
 384 {
 385         /* same dir for all commands */
 386         if (!strcmp(var, "buildid.dir")) {
 387                 const char *dir = perf_config_dirname(var, value);
 388
 389                 if (!dir)
 390                         return -1;
 391                 strncpy(buildid_dir, dir, MAXPATHLEN-1);
 392                 buildid_dir[MAXPATHLEN-1] = '\0';
 393         }
 394
 395         return 0;
 396 }
 397
 398 static int perf_default_core_config(const char *var __maybe_unused,
 399                                     const char *value __maybe_unused)
 400 {
 401         /* Add other config variables here. */
 402         return 0;
 403 }
 404
 405 static int perf_ui_config(const char *var, const char *value)
 406 {
 407         /* Add other config variables here. */
 408         if (!strcmp(var, "ui.show-headers")) {
 409                 symbol_conf.show_hist_headers = perf_config_bool(var, value);
 410                 return 0;
 411         }
 412         return 0;
 413 }
 414
 415 int perf_default_config(const char *var, const char *value,
 416                         void *dummy __maybe_unused)
 417 {
 418         if (!prefixcmp(var, "core."))
 419                 return perf_default_core_config(var, value);
 420
 421         if (!prefixcmp(var, "hist."))
 422                 return perf_hist_config(var, value);
 423
 424         if (!prefixcmp(var, "ui."))
 425                 return perf_ui_config(var, value);
 426
 427         if (!prefixcmp(var, "call-graph."))
 428                 return perf_callchain_config(var, value);
 429
 430         if (!prefixcmp(var, "llvm."))
 431                 return perf_llvm_config(var, value);
 432
 433         if (!prefixcmp(var, "buildid."))
 434                 return perf_buildid_config(var, value);
 435
 436         /* Add other config variables here. */
 437         return 0;
 438 }
 439
 440 static int perf_config_from_file(config_fn_t fn, const char *filename, void *data)
 441 {
 442         int ret;
 443         FILE *f = fopen(filename, "r");
 444
 445         ret = -1;
 446         if (f) {
 447                 config_file = f;
 448                 config_file_name = filename;
 449                 config_linenr = 1;
 450                 config_file_eof = 0;
 451                 ret = perf_parse_file(fn, data);
 452                 fclose(f);
 453                 config_file_name = NULL;
 454         }
 455         return ret;
 456 }
 457
 458 const char *perf_etc_perfconfig(void)
 459 {
 460         static const char *system_wide;
 461         if (!system_wide)
 462                 system_wide = system_path(ETC_PERFCONFIG);
 463         return system_wide;
 464 }
 465
 466 static int perf_env_bool(const char *k, int def)
 467 {
 468         const char *v = getenv(k);
 469         return v ? perf_config_bool(k, v) : def;
 470 }
 471
 472 static int perf_config_system(void)
 473 {
 474         return !perf_env_bool("PERF_CONFIG_NOSYSTEM", 0);
 475 }
 476
 477 static int perf_config_global(void)
 478 {
 479         return !perf_env_bool("PERF_CONFIG_NOGLOBAL", 0);
 480 }
 481
 482 static struct perf_config_section *find_section(struct list_head *sections,
 483                                                 const char *section_name)
 484 {
 485         struct perf_config_section *section;
 486
 487         list_for_each_entry(section, sections, node)
 488                 if (!strcmp(section->name, section_name))
 489                         return section;
 490
 491         return NULL;
 492 }
 493
 494 static struct perf_config_item *find_config_item(const char *name,
 495                                                  struct perf_config_section *section)
 496 {
 497         struct perf_config_item *item;
 498
 499         list_for_each_entry(item, &section->items, node)
 500                 if (!strcmp(item->name, name))
 501                         return item;
 502
 503         return NULL;
 504 }
 505
 506 static struct perf_config_section *add_section(struct list_head *sections,
 507                                                const char *section_name)
 508 {
 509         struct perf_config_section *section = zalloc(sizeof(*section));
 510
 511         if (!section)
 512                 return NULL;
 513
 514         INIT_LIST_HEAD(&section->items);
 515         section->name = strdup(section_name);
 516         if (!section->name) {
 517                 pr_debug("%s: strdup failed\n", __func__);
 518                 free(section);
 519                 return NULL;
 520         }
 521
 522         list_add_tail(&section->node, sections);
 523         return section;
 524 }
 525
 526 static struct perf_config_item *add_config_item(struct perf_config_section *section,
 527                                                 const char *name)
 528 {
 529         struct perf_config_item *item = zalloc(sizeof(*item));
 530
 531         if (!item)
 532                 return NULL;
 533
 534         item->name = strdup(name);
 535         if (!item->name) {
 536                 pr_debug("%s: strdup failed\n", __func__);
 537                 free(item);
 538                 return NULL;
 539         }
 540
 541         list_add_tail(&item->node, &section->items);
 542         return item;
 543 }
 544
 545 static int set_value(struct perf_config_item *item, const char *value)
 546 {
 547         char *val = strdup(value);
 548
 549         if (!val)
 550                 return -1;
 551
 552         zfree(&item->value);
 553         item->value = val;
 554         return 0;
 555 }
 556
 557 static int collect_config(const char *var, const char *value,
 558                           void *perf_config_set)
 559 {
 560         int ret = -1;
 561         char *ptr, *key;
 562         char *section_name, *name;
 563         struct perf_config_section *section = NULL;
 564         struct perf_config_item *item = NULL;
 565         struct perf_config_set *set = perf_config_set;
 566         struct list_head *sections;
 567
 568         if (set == NULL)
 569                 return -1;
 570
 571         sections = &set->sections;
 572         key = ptr = strdup(var);
 573         if (!key) {
 574                 pr_debug("%s: strdup failed\n", __func__);
 575                 return -1;
 576         }
 577
 578         section_name = strsep(&ptr, ".");
 579         name = ptr;
 580         if (name == NULL || value == NULL)
 581                 goto out_free;
 582
 583         section = find_section(sections, section_name);
 584         if (!section) {
 585                 section = add_section(sections, section_name);
 586                 if (!section)
 587                         goto out_free;
 588         }
 589
 590         item = find_config_item(name, section);
 591         if (!item) {
 592                 item = add_config_item(section, name);
 593                 if (!item)
 594                         goto out_free;
 595         }
 596
 597         ret = set_value(item, value);
 598         return ret;
 599
 600 out_free:
 601         free(key);
 602         return -1;
 603 }
 604
 605 static int perf_config_set__init(struct perf_config_set *set)
 606 {
 607         int ret = -1;
 608         const char *home = NULL;
 609
 610         /* Setting $PERF_CONFIG makes perf read _only_ the given config file. */
 611         if (config_exclusive_filename)
 612                 return perf_config_from_file(collect_config, config_exclusive_filename, set);
 613         if (perf_config_system() && !access(perf_etc_perfconfig(), R_OK)) {
 614                 if (perf_config_from_file(collect_config, perf_etc_perfconfig(), set) < 0)
 615                         goto out;
 616         }
 617
 618         home = getenv("HOME");
 619         if (perf_config_global() && home) {
 620                 char *user_config = strdup(mkpath("%s/.perfconfig", home));
 621                 struct stat st;
 622
 623                 if (user_config == NULL) {
 624                         warning("Not enough memory to process %s/.perfconfig, "
 625                                 "ignoring it.", home);
 626                         goto out;
 627                 }
 628
 629                 if (stat(user_config, &st) < 0)
 630                         goto out_free;
 631
 632                 if (st.st_uid && (st.st_uid != geteuid())) {
 633                         warning("File %s not owned by current user or root, "
 634                                 "ignoring it.", user_config);
 635                         goto out_free;
 636                 }
 637
 638                 if (!st.st_size)
 639                         goto out_free;
 640
 641                 ret = perf_config_from_file(collect_config, user_config, set);
 642
 643 out_free:
 644                 free(user_config);
 645         }
 646 out:
 647         return ret;
 648 }
 649
 650 struct perf_config_set *perf_config_set__new(void)
 651 {
 652         struct perf_config_set *set = zalloc(sizeof(*set));
 653
 654         if (set) {
 655                 INIT_LIST_HEAD(&set->sections);
 656                 if (perf_config_set__init(set) < 0) {
 657                         perf_config_set__delete(set);
 658                         set = NULL;
 659                 }
 660         }
 661
 662         return set;
 663 }
 664
 665 int perf_config(config_fn_t fn, void *data)
 666 {
 667         int ret = 0;
 668         char key[BUFSIZ];
 669         struct perf_config_section *section;
 670         struct perf_config_item *item;
 671
 672         if (config_set == NULL)
 673                 return -1;
 674
 675         perf_config_set__for_each_entry(config_set, section, item) {
 676                 char *value = item->value;
 677
 678                 if (value) {
 679                         scnprintf(key, sizeof(key), "%s.%s",
 680                                   section->name, item->name);
 681                         ret = fn(key, value, data);
 682                         if (ret < 0) {
 683                                 pr_err("Error: wrong config key-value pair %s=%s\n",
 684                                        key, value);
 685                                 break;
 686                         }
 687                 }
 688         }
 689
 690         return ret;
 691 }
 692
 693 void perf_config__init(void)
 694 {
 695         if (config_set == NULL)
 696                 config_set = perf_config_set__new();
 697 }
 698
 699 void perf_config__exit(void)
 700 {
 701         perf_config_set__delete(config_set);
 702         config_set = NULL;
 703 }
 704
 705 void perf_config__refresh(void)
 706 {
 707         perf_config__exit();
 708         perf_config__init();
 709 }
 710
 711 static void perf_config_item__delete(struct perf_config_item *item)
 712 {
 713         zfree(&item->name);
 714         zfree(&item->value);
 715         free(item);
 716 }
 717
 718 static void perf_config_section__purge(struct perf_config_section *section)
 719 {
 720         struct perf_config_item *item, *tmp;
 721
 722         list_for_each_entry_safe(item, tmp, &section->items, node) {
 723                 list_del_init(&item->node);
 724                 perf_config_item__delete(item);
 725         }
 726 }
 727
 728 static void perf_config_section__delete(struct perf_config_section *section)
 729 {
 730         perf_config_section__purge(section);
 731         zfree(&section->name);
 732         free(section);
 733 }
 734
 735 static void perf_config_set__purge(struct perf_config_set *set)
 736 {
 737         struct perf_config_section *section, *tmp;
 738
 739         list_for_each_entry_safe(section, tmp, &set->sections, node) {
 740                 list_del_init(&section->node);
 741                 perf_config_section__delete(section);
 742         }
 743 }
 744
 745 void perf_config_set__delete(struct perf_config_set *set)
 746 {
 747         if (set == NULL)
 748                 return;
 749
 750         perf_config_set__purge(set);
 751         free(set);
 752 }
 753
 754 /*
 755  * Call this to report error for your variable that should not
 756  * get a boolean value (i.e. "[my] var" means "true").
 757  */
 758 int config_error_nonbool(const char *var)
 759 {
 760         return error("Missing value for '%s'", var);
 761 }
 762
 763 void set_buildid_dir(const char *dir)
 764 {
 765         if (dir)
 766                 scnprintf(buildid_dir, MAXPATHLEN-1, "%s", dir);
 767
 768         /* default to $HOME/.debug */
 769         if (buildid_dir[0] == '\0') {
 770                 char *home = getenv("HOME");
 771
 772                 if (home) {
 773                         snprintf(buildid_dir, MAXPATHLEN-1, "%s/%s",
 774                                  home, DEBUG_CACHE_DIR);
 775                 } else {
 776                         strncpy(buildid_dir, DEBUG_CACHE_DIR, MAXPATHLEN-1);
 777                 }
 778                 buildid_dir[MAXPATHLEN-1] = '\0';
 779         }
 780         /* for communicating with external commands */
 781         setenv("PERF_BUILDID_DIR", buildid_dir, 1);
 782 }